I’m usually pretty immune to this sort of thing. I don’t want to dazzle my students with math. I want them to engage with math and sometimes the spectacle just intimidates them or makes math seem all the more foreign and unknowable.

I gave them the weekend. I gave them a week’s worth of homework credit. I let them work with a partner.

33% of the class submitted data. That’s a pity. Even worse is the difference between the data I personally gathered last September (blue diamonds) and the noise my students submitted (pink squares) some of which was almost laughably fabricated. (As in, I laughed when I saw it.)

For perspective, I have one really exceptional outlier out of the thirty-six transactions I recorded: the person who took six minutes to purchase twenty items. It was a disastrous exchange featuring a price check and a ripped register tape. It was so bad that people happily fled that customer’s line for longer ones.

Out of my students’ thirty-two data points, they observed six transactions that were even more abnormal than that one, including one incredible checker who managed to ring up one hundred items in just eighty-one seconds.

My immediate thought when I first watched the video was to recreate the scenario in my own room which has a drop ceiling. Once the students are set on their solution, we move the tile and find a bag of chocolates shaped like golden bars for the class to enjoy.